Hydrangea plant named ‘H218922’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘H218922’, characterized by its upright and uniformly mounded plant habit; vigorous growth habit and rapid growth rate; freely branching habit with strong, thick and sturdy stems; freely and uniformly flowering habit; mophead-type inflorescences with numerous dark red purple-colored sterile flowers; and good postproduction longevity.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘H218922’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar ofHydrangea plant, botanically known as Hydrangea macrophylla,commercially referred to as a mophead-type Hydrangea and hereinafterreferred to by the name ‘H218922’.

The new Hydrangea plant is a product of a planned breeding programconducted by the Inventor in De Kwakel, The Netherlands and Lengerich,Germany. The objective of the breeding program was to create new strongand freely-branching Hydrangea plants with strong sturdy stems, uniformflowering habit, large inflorescences with numerous showy sterileflowers, attractive sterile flower color and good postproductionlongevity.

The new Hydrangea plant originated from a cross-pollination made by theInventor in March, 2013 in De Kwakel, The Netherlands, of Hydrangeamacrophylla ‘Paris Rapa’, disclosed in U.S. Plant Pat. No. 10,906, asthe female, or seed, parent with Hydrangea macrophylla ‘Dark Angel’, notpatented, as the male, or pollen, parent. The new Hydrangea plant wasdiscovered and selected by the Inventor as a single flowering plant fromwithin the progeny of the stated cross-pollination in a controlledgreenhouse environment in Lengerich, Germany in March, 2014.

Asexual reproduction of the new Hydrangea plant by vegetative tipcuttings in a controlled environment in De Kwakel, The Netherlands sinceApril, 2015 has shown that the unique features of this new Hydrangeaplant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possiblecombinations of environmental conditions and cultural practices. Thephenotype may vary somewhat with variations in environmental conditionssuch as temperature and light intensity without, however, any variancein genotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘H218922’. These characteristics incombination distinguish ‘H218922’ as a new and distinct Hydrangea plant:

-   -   1. Upright and uniformly mounded plant habit.    -   2. Vigorous growth habit and rapid growth rate.    -   3. Freely branching habit with strong, thick and sturdy stems.    -   4. Freely and uniformly flowering habit.    -   5. Mophead-type inflorescences with numerous dark red        purple-colored sterile flowers.    -   6. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the femaleparent, ‘Paris Rapa’. Plants of the new Hydrangea differ primarily fromplants of ‘Paris Rapa’ in sterile flower color as plants of the newHydrangea have dark red purple-colored sterile flowers whereas plants of‘Paris Rapa’ have dark red-colored sterile flowers.

Plants of the new Hydrangea can be compared to plants of the maleparent, ‘Dark Angel’. Plants of the new Hydrangea differ primarily fromplants of ‘Dark Angel’ in branching habit as plants of the new Hydrangeaare more freely branching than plants of ‘Dark Angel’.

Plants of the new Hydrangea can be compared to plants of the Hydrangeamacrophylla ‘HBA215910’, disclosed in U.S. Plant Pat. No. 29,171. Inside-by-side comparisons, plants of the new Hydrangea differ primarilyfrom plants of ‘HBA215910’ in the following characteristics:

-   -   1. Plants of the new Hydrangea are more vigorous and broader        than plants of ‘HBA215910’.    -   2. Plants of the new Hydrangea are more freely branching than        plants of ‘HBA215910’.    -   3. Plants of the new Hydrangea have taller panicles than plants        of ‘HBA215910’.    -   4. Plants of the new Hydrangea have dark red purple-colored        sterile flowers whereas plants of ‘HBA215910’ have dark red        purple-colored sterile flowers with green-colored sectors.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance ofthe new Hydrangea plant showing the colors as true as it is reasonablypossible to obtain in colored reproductions of this type. Colors in thephotographs may differ from the color values cited in the detailedbotanical description which accurately describe the colors of the newHydrangea plant.

The photograph on the first sheet is a side perspective view of atypical flowering plant of ‘H218922’.

The photograph on the second sheet is a close-up view of a typicalinflorescence of ‘H218922’.

The photograph on the third sheet is a top perspective view of a typicalflowering plant of ‘H218922’ that has been “blued” (left) that is,treated with aluminum sulfate, and a top perspective view of a typicalflowering plant of ‘H218922’ that has not been “blued” (right) that is,not treated with aluminum sulfate.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photographs and in the followingdescription were grown during the late spring and early summer in 13-cmcontainers in a glass-covered greenhouse in De Kwakel, The Netherlandsand under cultural practices typical of commercial Hydrangea production.During the production of the plants, day and night temperatures averaged17° C. Plants of the new Hydrangea were one year old when thephotographs and description were taken. Plants of the new Hydrangea canbe successfully treated with aluminum sulfate to “blue” theinflorescences. In the following description, color references are madeto The Royal Horticultural Society Colour Chart, 2015 Edition, exceptwhere general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘H218922’.-   Parentage:    -   -   Female, or seed, parent.—Hydrangea macrophylla ‘Paris Rapa’,            disclosed in U.S. Plant Pat. No. 10,906.        -   Male, or pollen, parent.—Hydrangea macrophylla ‘Dark Angel’,            not patented.-   Propagation:    -   -   Type cutting.—By vegetative tip cuttings.        -   Time to initiate roots, summer.—About two weeks at            temperatures about 23° C.        -   Time to initiate roots, winter.—About 18 days at            temperatures about 20° C.        -   Time to produce a rooted young plant, summer.—About four            weeks at temperatures about 23° C.        -   Time to produce a rooted young plant, winter.—About five            weeks at temperatures about 20° C.        -   Root description.—Thick; typically whitish brown in color,            actual color of the roots is dependent on substrate            composition, water quality, fertilizer type and formulation,            substrate temperature and physiological age of roots.        -   Rooting habit.—Freely branching; dense.-   Plant description:    -   -   Plant and growth habit.—Upright and uniformly mounded plant            habit; strong and sturdy stems; rapid growth rate and            vigorous growth habit.        -   Plant height.—About 30 cm to 35 cm.        -   Plant diameter or area of spread.—About 60 cm.-   Lateral branch description:    -   -   Branching habit.—Freely branching habit; when pinched, about            ten lateral branches develop per plant.        -   Length.—About 25 cm.        -   Diameter.—About 8 mm.        -   Internode length.—About 5 cm to 7 cm.        -   Texture.—Smooth, glabrous; fully developed, woody.        -   Aspect.—Upright to about 20° from vertical.        -   Strength.—Strong, sturdy.        -   Color.—When developing: Close to 146C; at internodes, close            to 187A; lenticels, close to 187A. Developed: Close to 146C;            at the internodes, close to 187A; when woody, close to 177D;            lenticels, close to 187A.-   Leaf description:    -   -   Arrangement.—Opposite, simple.        -   Length.—About 10 cm to 12 cm.        -   Width.—About 7 cm to 8 cm.        -   Shape.—Ovate.        -   Apex.—Acute to acuminate.        -   Base.—Obtuse.        -   Margin.—Dentate to serrate.        -   Texture, upper and lower surfaces.—Rugose, glabrous.        -   Venation pattern.—Pinnate.        -   Color.—Developing leaves, upper surface: Close to 137A.            Developing leaves, lower surface: Close to 138B. Fully            expanded leaves, upper surface: Close to NN137A; venation,            close to 145B. Fully expanded leaves, lower surface: Close            to 138B; venation, close to 145C.        -   Petioles.—Length: About 3 cm to 5 cm. Diameter: About 5 mm.            Texture, upper and lower surfaces: Smooth, glabrous. Color,            upper surface: Close to 145B. Color, lower surface: Close to            145C.-   Flower description:    -   -   Flower type and habit.—Showy sterile flowers and small            inconspicuous fertile flowers arranged on mophead-type            terminal panicles; panicles globular in shape; flowers face            upright to outwardly depending on their position in the            inflorescence.        -   Fragrance.—None detected.        -   Natural flowering season.—Plants begin flowering about one            year after planting; flowering begins in the early summer            and is continuous throughout the summer in Northern Europe.        -   Flower longevity.—Fertile flowers last about one month on            the plant, fertile flowers not persistent; sterile flowers            last about four months on the plant, sterile flowers            persistent.        -   Quantity of flowers.—Freely flowering habit; about 40            fertile flowers per panicle and about 100 sterile flowers            per panicle.        -   Panicle height.—About 8 cm to 10 cm.        -   Panicle diameter.—About 18 cm to 22 cm.        -   Fertile flower buds.—Length: About 3 mm. Diameter: About            3 mm. Shape: Flattened globular. Color: Close to N80B and            150D.        -   Sterile flower buds.—Length: About 3 mm. Diameter: About            3 mm. Shape: Flattened globular. Color: Close to 150D and            73B.        -   Fertile flower diameter.—About 6 mm.        -   Fertile flower depth (height).—About 5 mm.        -   Sterile flower diameter.—About 4 cm to 5 cm.        -   Sterile flower depth (height).—About 1 cm.        -   Petals, fertile flowers.—Quantity and arrangement: Four in a            single whorl. Length: About 3.5 mm. Width: About 2 mm.            Shape: Ovate. Apex: Acute. Base: Obtuse. Margin: Entire.            Texture, upper and lower surfaces: Smooth, glabrous. Color:            When opening, upper and lower surfaces: Close to N80B and            150D. Fully opened, upper and lower surfaces: Close to N80B            and 150D; color does not change with development.        -   Petals, sterile flowers.—Quantity and arrangement: Four or            five in a single whorl. Length: About 3.5 mm. Width: About            2 mm. Shape: Ovate. Apex: Acute. Base: Attenuate. Margin:            Entire. Texture, upper and lower surfaces: Smooth, glabrous.            Color: When opening, upper and lower surfaces: Close to 62C.            Fully opened, upper and lower surfaces: Close to 62C; color            does not change with development.        -   Sepals, fertile flowers.—Quantity and arrangement: Five in a            single whorl. Length: About 2 mm. Width: About 2 mm. Shape:            Ovate. Apex: Acute. Base: Obtuse. Margin: Entire. Texture,            upper and lower surfaces: Smooth, glabrous. Color: When            opening and fully opened, upper surface: Close to 144B;            color does not change with development. When opening and            fully opened, lower surface: Close to 144B; color does not            change with development.        -   Sepals, sterile flowers.—Quantity and arrangement: Four in a            single whorl. Length: About 2 cm to 2.5 cm. Width: About 2            cm to 2.5 cm. Shape: Deltoid. Apex: Acute. Base: Obtuse.            Margin: Serrate to serrulate. Texture, upper surface:            Smooth, glabrous. Texture, lower surface: Rugose, glabrous.            Color: When opening, upper and lower surfaces: Close to            144B. Fully opened, upper surface: Close to N57B; towards            the base, close to 65A; with development, color towards the            apex becoming closer to 144B; when “blued”, becoming closer            to 72B and towards the apex, close to 144B. Fully opened,            lower surface: Close to N57D and 144D; color does not change            with development.        -   Pedicels, fertile flowers.—Length: About 4 mm. Diameter:            About 1 mm. Strength: Moderately strong. Aspect: Mostly            upright. Texture: Smooth, glabrous. Color: Close to 144C.        -   Pedicels, sterile flowers.—Length: About 2.5 cm. Diameter:            About 1.5 mm. Strength: Strong. Aspect: Erect to about 45°            from vertical. Texture: Smooth, glabrous. Color: Close to            N57C.        -   Reproductive organs, fertile flowers.—Stamens: Quantity per            flower: Eight. Filament length: About 1 mm. Filament color:            Close to 75C. Anther length: About 1 mm. Anther shape:            Conical. Anther color: Close to N75D. Pollen amount:            Abundant. Pollen color: Close to 155D. Pistils: Pistil            quantity per flower: Three. Pistil length: About 1 mm.            Stigma shape: Oval. Stigma color: Close to 73D. Style            length: About 1 mm. Style color: Close to 150D. Ovary color:            Close to 150D.        -   Reproductive organs, sterile flowers.—Stamens: Quantity per            flower: About three or four. Filament length: About 1 mm.            Filament color: Close to 75C. Anther length: About 1 mm.            Anther shape: Conical. Anther color: Close to N75D. Pollen            amount: Abundant. Pollen color: Close to 155D. Pistils: To            date, pistil development has not been observed on plants of            the new Hydrangea.        -   Seeds, only produced by fertile flowers.—Quantity per            fertile flower: About 20 to 30. Length: About 0.5 mm.            Diameter: About 0.1 mm. Color: Close to 200C.-   Pathogen & pest resistance: Under commercial production conditions,    plants of the new Hydrangea have not been observed to be resistant    to pathogens and pests common to Hydrangea plants to date.-   Temperature tolerance: Plants of the new Hydrangea have been shown    to be tolerant to temperatures ranging from about 3° C. to about 38°    C.

It is claimed:
 1. A new and distinct Hydrangea plant named ‘H218922’ asillustrated and described.